Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images
The estimation of Above-Ground Biomass (AGB) in Amorphophallus konjac (Konjac) is essential for field management and yield prediction. While previous research has demonstrated the efficacy of Unmanned Aerial Vehicle (UAV) RGB imagery in estimating AGB for monoculture crops, the applicability of thes...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-03-01
|
| Series: | Drones |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2504-446X/9/3/220 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850204042018422784 |
|---|---|
| author | Ziyi Yang Hongjuan Qi Kunrong Hu Weili Kou Weiheng Xu Huan Wang Ning Lu |
| author_facet | Ziyi Yang Hongjuan Qi Kunrong Hu Weili Kou Weiheng Xu Huan Wang Ning Lu |
| author_sort | Ziyi Yang |
| collection | DOAJ |
| description | The estimation of Above-Ground Biomass (AGB) in Amorphophallus konjac (Konjac) is essential for field management and yield prediction. While previous research has demonstrated the efficacy of Unmanned Aerial Vehicle (UAV) RGB imagery in estimating AGB for monoculture crops, the applicability of these methods to AGB estimation in Konjac remains uncertain due to its distinct morphological traits and prevalent intercropping practices with maize. Additionally, the Vegetation Indices (VIs) and Texture Features (TFs) obtained from UAV-based RGB imagery exhibit significant redundancy, raising concerns about whether the selected optimal variables can maintain estimation accuracy. Therefore, this study assessed the effectiveness of Variable Selection Using Random Forests (VSURF) and Principal Component Analysis (PCA) in variable selection and compared the performance of Stepwise Multiple Linear Regression (SMLR) with four Machine Learning (ML) regression techniques: Random Forest Regression (RFR), Extreme Gradient Boosting Regression (XGBR), Partial Least Squares Regression (PLSR), and Support Vector Regression (SVR), as well as Deep Learning (DL), in estimating the AGB of Konjac based on the selected features. The results indicate that the integration (PCA_(PCA_VIs+PCA_TFs)) of PCA-based VIs and PCA-based TFs using PCA achieved the best prediction accuracy (R<sup>2</sup> = 0.96, RMSE = 0.08 t/hm<sup>2</sup>, MAE = 0.06 t/hm<sup>2</sup>) with SVR. In contrast, the DL model derived from AlexNet, combined with RGB imagery, yielded moderate predictive accuracy (R<sup>2</sup> = 0.72, RMSE = 0.21 t/hm<sup>2</sup>, MAE = 0.17 t/hm<sup>2</sup>) compared with the optimal ML model. Our findings suggest that ML regression techniques, combined with appropriate variable-selected approaches, outperformed DL techniques in estimating the AGB of Konjac. This study not only provides new insights into AGB estimation in Konjac but also offers valuable guidance for estimating AGB in other crops, thereby advancing the application of UAV technology in crop biomass estimation. |
| format | Article |
| id | doaj-art-04c30d22e4c54d51aee4218ceac7c7b1 |
| institution | OA Journals |
| issn | 2504-446X |
| language | English |
| publishDate | 2025-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Drones |
| spelling | doaj-art-04c30d22e4c54d51aee4218ceac7c7b12025-08-20T02:11:22ZengMDPI AGDrones2504-446X2025-03-019322010.3390/drones9030220Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB ImagesZiyi Yang0Hongjuan Qi1Kunrong Hu2Weili Kou3Weiheng Xu4Huan Wang5Ning Lu6College of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaAgricultural and Rural Development Service Center of Housuo Town, Qujing 655501, ChinaCollege of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaCollege of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaCollege of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaCollege of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaCollege of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming 650223, ChinaThe estimation of Above-Ground Biomass (AGB) in Amorphophallus konjac (Konjac) is essential for field management and yield prediction. While previous research has demonstrated the efficacy of Unmanned Aerial Vehicle (UAV) RGB imagery in estimating AGB for monoculture crops, the applicability of these methods to AGB estimation in Konjac remains uncertain due to its distinct morphological traits and prevalent intercropping practices with maize. Additionally, the Vegetation Indices (VIs) and Texture Features (TFs) obtained from UAV-based RGB imagery exhibit significant redundancy, raising concerns about whether the selected optimal variables can maintain estimation accuracy. Therefore, this study assessed the effectiveness of Variable Selection Using Random Forests (VSURF) and Principal Component Analysis (PCA) in variable selection and compared the performance of Stepwise Multiple Linear Regression (SMLR) with four Machine Learning (ML) regression techniques: Random Forest Regression (RFR), Extreme Gradient Boosting Regression (XGBR), Partial Least Squares Regression (PLSR), and Support Vector Regression (SVR), as well as Deep Learning (DL), in estimating the AGB of Konjac based on the selected features. The results indicate that the integration (PCA_(PCA_VIs+PCA_TFs)) of PCA-based VIs and PCA-based TFs using PCA achieved the best prediction accuracy (R<sup>2</sup> = 0.96, RMSE = 0.08 t/hm<sup>2</sup>, MAE = 0.06 t/hm<sup>2</sup>) with SVR. In contrast, the DL model derived from AlexNet, combined with RGB imagery, yielded moderate predictive accuracy (R<sup>2</sup> = 0.72, RMSE = 0.21 t/hm<sup>2</sup>, MAE = 0.17 t/hm<sup>2</sup>) compared with the optimal ML model. Our findings suggest that ML regression techniques, combined with appropriate variable-selected approaches, outperformed DL techniques in estimating the AGB of Konjac. This study not only provides new insights into AGB estimation in Konjac but also offers valuable guidance for estimating AGB in other crops, thereby advancing the application of UAV technology in crop biomass estimation.https://www.mdpi.com/2504-446X/9/3/220konjacabove-ground biomassregression techniquesUAV-based RGBdeep learning |
| spellingShingle | Ziyi Yang Hongjuan Qi Kunrong Hu Weili Kou Weiheng Xu Huan Wang Ning Lu Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images Drones konjac above-ground biomass regression techniques UAV-based RGB deep learning |
| title | Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images |
| title_full | Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images |
| title_fullStr | Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images |
| title_full_unstemmed | Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images |
| title_short | Estimation of Amorphophallus Konjac Above-Ground Biomass by Integrating Spectral and Texture Information from Unmanned Aerial Vehicle-Based RGB Images |
| title_sort | estimation of amorphophallus konjac above ground biomass by integrating spectral and texture information from unmanned aerial vehicle based rgb images |
| topic | konjac above-ground biomass regression techniques UAV-based RGB deep learning |
| url | https://www.mdpi.com/2504-446X/9/3/220 |
| work_keys_str_mv | AT ziyiyang estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT hongjuanqi estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT kunronghu estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT weilikou estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT weihengxu estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT huanwang estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages AT ninglu estimationofamorphophalluskonjacabovegroundbiomassbyintegratingspectralandtextureinformationfromunmannedaerialvehiclebasedrgbimages |